James o



J. o. DRAPBR;

`STEAM BOILER.

(No Model.)

No. 312,447. .Patented Feb. 17,1885.

i '/5 Y 'lil' WITNESEESI `UNITED ASTATES PATENT OFFICE.

JAMES O. DRAPER, OF PAWTUCKET, RHODE ISLAND.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent Noa 312,447, dated February 17, 1885.

i Application med July 14, 1884. (No moan.)

To all whoml it may concern.-

Be it known that I, JAMES O. DRAPER, of Pawtucket, in the county of Providence and State of "Rhode Island, have invented an Improvement in Steam-Boilers, of which the following is a specication.

My invention consists in the combination of a revolublecover provided with a covered opening with the draft-tubes of a steam-boiler, whereby, without removing the main cover, ready access maybe had to the boiler-fines for the purpose of cleaning the same.

Figure 1 is a perspective view showing a set boiler provided with my improvement, the revoluble cover being broken away at Vone side to show the upper end of the boiler. Fig. 2 is a central vertical section of thesame. Fig. 3 is a top view of the boiler with the cover removed.

In the accompanying drawings, A is the boiler; B, the brick setting or'outer case of the boiler; C, the chimney; D, the circular fire-chamber; E, the ash-pit; F, the direct flue to the chimney, and G the circulatingflue around the upper portion of the boiler.

The boiler A is provided with the upright ilues a a, and the outer shell, b, ofv the boiler is'eXtended upward above the upper head of the same,lso as to form the sides of a circular chamber, c, the top of which is formed by the under surface of the rotary cover H.

Over the boiler-head, within the chamber c, is placed the perforated plate I, provided with an attached guiding-rod, e, and over the plate I, and resting upon the same, is placed the perforated plate I', provided with the guiding-rod e,the plates I I being made capable of a limited movement in the direction of the oppositely-attached guiding-rods, and the 40 perforations d d in the respective plates loeing4 made to register with each other, and with the continuation ofthe bore of the lues a a at the extreme of the opposite movement of the plates, as shown in Fig. 2, and to close over each other, and thus form contracted openings in the line of the dues, adapted to check the upward -movement of the products of combustion within the same when moved in opposite directions from the registering-point, 5o as shown in Fig. 3.

Upon the top of the brick-work casing B r is secured the bed-plate J, provided with an annular groove, f, in the bottom of which I preferably place a continuous layer of sand, g, and over the top of the boiler, and covering the chamber c and outer flue, G, I place the circular rotary cover H, the upper boundary-edge of which is provided with the bevel-gear h., made to engage with the operating-pinion t', located at the inner end of the 6c crank-shaft 7c, which is held for rotation in the journal-box K,attached to the inclosing brick- Work, as shown in Fig. l. The cover H may thus be rotated in either directionby means of the crank m, a downwardly projecting flange, a, which enters the groove f of the bedllplate J and rests on the sand g, serving to form a close joint adapted to prevent the escape of the products of combustion from under the cover H. The cover H is also provided with a sector-formed opening, r, and around the edge of the opening is formed a groove, s, within which is also placed a layer of sand, t, and the removable cover L, made in sector "form, is provided at its under side and near its edge with the downwardly-pro jecting flange u, which is adapted to enter the groove s, and rest upon the sand layer t, thussecuring a closed joint around the opening o". The sector-formed cover L is also provided with a ring or handle, o, by means of which the cover may be readily removed from the opening r, and after such removal, by rotating the cover H, access may be had to the outer flue, G, and to all the flues a a of the boiler.

The brick-work casing is constructed with an inwardly-projecting iiange, o, made to t the cylindrical shell of the boiler, to which are secured the brackets p p p, by means of 9o which the boiler will be supported upon theA flange o.

In the upright extension of the shell of the boiler is made a draft-opening., Z, between which and the chimney-flue M is placed the 95 upright partition N, which serves to prevent the products of combustion from passing from the opening Z direct to the chimney-flue, and causes the same to circulate around the upper end of the boiler, and to pass under the comparatively short upright partition O into the chimney-flue, thus holding the heat around the upper portion of the boiler. With this construction it Will be readily seen that upon r0- tating the cover H so that the sector-opening r Will come immediately over the spacew between the vertical partitions N and O a communication will be established from the charnber c direct to the chimney-flue, as shown in Fig. 2, and by moving the opening 1 past the partition N and over the opening Z made in the upward extension of the shell of the boiler an additional space will be formed for the passage of the heated products of combustion to the circulating-Hue G around the upper portion of the boiler, and thus by means of the cover H the draft through the flues a a and around the boiler may be desirably controlled.

claim as my inventionl. The combination of the upright boiler A, provided with the tlues ca a, and the sliding plates I I, provided With perforations d el', e which at one position of the sliding plates are made to register with each other and with the openings of the boiler-lines, and at other positions of theplates serving to form a contracted opening for the iues,with the revolving cover H, provided with a covered opening, r, and means for revolving the cover H, substantially as described.

2. The combination of the upright boiler A, provided With the flues aa, with an outer case, B, cover H, having an opening, 1^, and also a cover, L, adapted to the same, and means for revolving the cover H, substantially as described.

3. The combination of the boiler A, provided With the nues a a, outer case, B, and the plate J, provided with an annular groove, f, with the revoluble cover H, provided with a flange, n, adapted to enter the groove f, and with an opening, 9", through which access may be had to the boiler-fines, and means for revolving the cover H, substantially as described.

JAMES O. DRAPER. 

